Synthesis and Biological Evaluation of Novel 2,4-Diaminoquinazoline Derivatives as SMN2 Promoter Activators for the Potential Treatment of Spinal Muscular Atrophy
摘要:
Proximal spinal muscular atrophy (SMA) is an autosomal recessive disorder characterized by death of motor neurons in the spinal cord that is caused by deletion and/or mutation of the survival motor neuron gene (SMN1). Adjacent to SMN1 are a variable number of copies of the SMN2 gene. The two genes essentially differ by a single nucleotide, which causes the majority of the RNA transcripts from SMN2 to lack exon 7. Although both SMN1 and SMN2 encode the same Smn protein amino acid sequence, the loss of SMN1 and incorrect splicing of SMN2 have the consequence that Smn protein levels are insufficient for the survival of motor neurons. The therapeutic goal of our medicinal chemistry effort was to identify small-molecule activators of the SMN2 promoter that, by up-regulating gene transcription, would produce greater quantities of full-length Smn protein. Our initial medicinal chemistry effort explored a series of C5 substituted benzyl ether based 2,4-diaminoquinazoline derivatives that were found to be potent activators of the SMN2 promoter; however, inhibition of DHFR was shown to be an off-target activity that was linked to ATP depletion. We used a structure-guided approach to overcome DHFR inhibition while retaining SMN2 promoter activation. A lead compound 11a was identified as having high potency (EC50 = 4 nM) and 2.3-fold induction of the SMN2 promoter. Compound Ila possessed desirable pharmaceutical properties, including excellent brain exposure and long brain half-life following oral dosing to mice. The piperidine compound Ila up-regulated expression of the mouse SMN gene in NSC-34 cells, a mouse motor neuron hybrid cell line. In type I SMA patient fibroblasts, compound Ila induced Smn in a dose-dependent manner when analyzed by immuno-blotting and increased the number of intranuclear particles called gems. The compound restored gems numbers in type I SMA patient fibroblasts to levels near unaffected genetic carriers of SMA.
The present invention includes compounds having structural formula (I), or pharmaceutically acceptable salts, solvate, and/or ester thereof. These compounds are useful as sweet flavor modifiers. The present invention also includes compositions comprising the present compounds and methods of enhancing the sweet taste of ingestible compositions. Furthermore, the present invention provides methods for preparing the compounds.
The present invention includes compounds having structural formula (I), or pharmaceutically acceptable salts, solvate, and/or ester thereof. These compounds are useful as sweet flavor modifiers. The present invention also includes compositions comprising the present compounds and methods of enhancing the sweet taste of ingestible compositions. Furthermore, the present invention provides methods for preparing the compounds.
Method of improving stability of sweet enhancer and composition containing stabilized sweet enhancer
申请人:Tachdjian Catherine
公开号:US09000054B2
公开(公告)日:2015-04-07
The present invention includes methods of stabilizing one or more sweet enhancers when they are exposed to a light source as well as liquid compositions containing one or more sweet enhancers and one or more photostabilizers.